title: Demonstration of the spin solar cell and spin photodiode effect.
abstract: Spin injection and extraction are at the core of semiconductor spintronics. Electrical injection is one method of choice for the creation of a sizeable spin polarization in a semiconductor, requiring especially tailored tunnel or Schottky barriers. Alternatively, optical orientation can be used to generate spins in semiconductors with significant spin-orbit interaction, if optical selection rules are obeyed, typically by using circularly polarized light at a well-defined wavelength. Here we introduce a novel concept for spin injection/extraction that combines the principle of a solar cell with the creation of spin accumulation. We demonstrate that efficient optical spin injection can be achieved with unpolarized light by illuminating a p-n junction where the p-type region consists of a ferromagnet. The discovered mechanism opens the window for the optical generation of a sizeable spin accumulation also in semiconductors without direct band gap such as Si or Ge.
authors.affiliation: Institut für Experimentelle und Angewandte Physik, Universität Regensburg, Regensburg, Germany. Bernhard.Endres@ur.de
authors.forename: B
authors.initials: B
authors.lastname: Endres
authors.forename: M
authors.initials: M
authors.lastname: Ciorga
authors.forename: M
authors.initials: M
authors.lastname: Schmid
authors.forename: M
authors.initials: M
authors.lastname: Utz
authors.forename: D
authors.initials: D
authors.lastname: Bougeard
authors.forename: D
authors.initials: D
authors.lastname: Weiss
authors.forename: G
authors.initials: G
authors.lastname: Bayreuther
authors.forename: C H
authors.initials: CH
authors.lastname: Back